PERMFILE47002

• Permit No: C1981014
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Section_Exhibit Name: EXHIBIT 18 GEOTECHNICAL INVESTIGATIONS
• Media Type: D
• Archive: No

• As shown on Figure 2, five different conditions were evaluated
for each specified pile height. These conditions consisted of
(1) effective stress analysis with pore pressure build up within
the fine refuse pond located at various distances from the
final toe location; (2) effective stress analysis with
piezometric surface located at ground surface (drain fully
functioning) with low strength subsurface soil layer and no fine
refuse; (3) effective stress analysis with pore pressure build
up to elevation 6300 (drain plugged with excessive infiltration
through pile) with no fine refuse pond; (4) piezometric surfaces
located at ground surface with high strength subsurface soils;
and (5) total stress analysis with and without fine cefuse pond
located near toe.
• Condition 1 was evaluated to determine how the location of the
fine refuse pond (low strength, high pore pressure area) would
effect the stability of the pile. Conditions 2 and 4 were
analyzed to determine if strength variation in the subsurface
soils would affect the stability of the pile. Condition 3 was
evaluated to determine what effect a plugged drain and very high
infiltcation rates would have on stability. Condition 5 was
evaluated to determine the effect of short-term stability (end of
construction).
The minimum factors of safety for each of the evaluated
conditions were determined using a computer-assisted limit
equilibrium method of slices. This particular program utilizes
• Spencer's methods of analysis. The program is capable of
analyzing stability conditions not only in circular modes of
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